GMC SUBURBAN INSTRUMENT CLUSTER GAUGE

Oil Pressure Gauge Maxed Out When Driving.

New Iac, Map Sensor, Egr, Thermostat, Fuel Filter And Tune Up. Tested Tps Tested Good. No Codes Showing Running Out Of Ideas And Money....

If The Coolant Is Compromised With The Addition Of An Oily Substance, Would This Cause Vehicle To Eventually Over Heat? After I Keep...